1. Field of the Invention
The present invention relates, in general, to mobile middleware, and, more particularly, to mobile middleware, a context monitoring method, a context-aware system, and a context-aware service provision method, which support energy-efficient context monitoring for context-aware application programs.
2. Description of the Related Art
A recent information communication paradigm that has arisen is ubiquitous computing, ubiquitous Networks, pervasive computing, etc. These terms indicate the same concept, wherein the term “ubiquitous” means that a user can easily obtain desired information anytime and anywhere. In the ubiquitous generation that will come in the future, smart objects, having a computing and communication ability, will have the characteristics of being aware of variation in dynamic environments and adapting themselves to such dynamic environmental variation, that is, context-aware characteristics.
A Personal Area Network (hereinafter referred to as a ‘PAN’) is core technology for realizing ubiquitous networks that will have context-aware characteristics. The term “PAN” refers to network technology that can be used within a short range around a person, and means technology for connecting various types of equipment to each other over a network by a distance of about 10 m from a person who uses the network. A person-centered PAN is suitable for context-aware applications, which provide suitable services depending on various types of context related to the behavior, physical conditions and environment of a user. In a PAN environment, a network is configured on the basis of a person, and thus a mobile device, which is portable, may be a core platform for receiving data from various sensors and providing user context information to the context-aware application programs. For example, it is possible to be aware of the context of a user through the collection and exchange of context information by a mobile communication terminal, and to provide information to context-aware application programs through processing, such as analysis and reasoning. The context-aware application programs can provide services suitable for the context of the user. In this case, mobile middleware capable of simultaneously and efficiently supporting a plurality of context-aware application programs is required.
However, conventional middleware supporting context-aware application programs merely provides a typical framework for a context-aware method, such as resource searching, data pre-processing, the generation and classification of feature values, and reasoning, but does not provide sufficient technology for supporting energy-efficient context monitoring. Further, data processing technology used in conventional middleware supports Structured Query Language (SQL)-based query models for data streams and database operations. This technology was developed to be applied in environments in which there are no restrictions on computing resources, like a high-performance server or a desk-top PC. That is, there is a problem in that the conventional middleware and data processing technology used therein are not suitable for the environment of mobile devices, in which limited energy is provided.
Therefore, energy-efficient mobile middleware capable of continuously monitoring data, provided by sensors, in the environment of mobile devices, on which serious resource limitations are imposed, is required.